le'lHl WWII } 1 m a O ‘f 3 93* ZS! llslllllllllzlfllfllllllllflfljljflllfllllllljflllzll LIBRARY Michigan State University This is to certify that the thesis entitled IN-SEASON WEIGHT TRAINING AND ITS EFFECTS ON HIGH SCHOOL BASKETBALL PLAYERS presented by Steven Boyd Mather has been accepted towards fulfillment of the requirements for M.A. the School of degree in Health Education, Counseling Psychology and Human Performance zgaaéééz¢;yié&fiZZLQZ14¢Zh_a/ Major professor Date%Y/é /7jl 0-7639 MS U is an Affirmative Action/Equal Opportunity Institution MSU LIBRARIES “ RETURNING MATERIALS: Place in book drop to remove this checkout from your record. FINES will be charged if book is returned after the date stamped below. 1’1 IN-SEASON WEIGHT TRAINING AND ITS EFFECTS ON HIGH SCHOOL BASKETBALL PLAYERS By Steven Boyd Mather A THESIS Submitted to Michigan State University in partial fulfillment of the requirements for the degree of MASTER OF ARTS School of Health Education, Counseling Psychology, and Human Performance 1988 51196] ABSTRACT IN-SEASON WEIGHT TRAINING AND ITS EFFECTS ON HIGH SCHOOL BASKETBALL PLAYERS By Steven Boyd Mather Eleven male high school basketball players were tested for leg strength and power. They then were divided into control and experi- mental groups. The experimental group participated in a weight training program in addition to their regular practice and game schedule. The controls were not involved in a weight training pro- gram prior to the season. Testing was conducted at the beginning, middle and end of the competitive season. Data were collected on peak torque and power. Peak torque was measured with a Cybex II dynamometer. Power was measured with a modified vertical jump test. Analyses showed no significant changes in peak torque or leg power throughout the sea- son for either group. It was concluded that the weight training load was not enough to produce significant strength gains. A motor learning model was advanced as a tentative explanation for the non- significant increase observed in leg power within the control group. DEDICATION This thesis is dedicated to my parents, P. Boyd and Darlene Mather, whose love and concern have provided countless opportunities for me, and my brother David, whose companionship and opinions I value so highly. ACKNOWLEDGEMENTS I would like to express my appreciation to all the people who helped me to complete this study. William W. Heusner, Ph.D., gave indispensable help in research design, statistical analysis, and writing of results whilst in the middle of a very heavy personal schedule. Jeffrey 5. Monroe, ATC, donated testing facilities and gave a great deal of practical advice and support, Dr. E. James Swenson, M.D., gave good practical suggestions for testing methods and was always supportive and helpful. Jeff Marmelstein, fellow athletic trainer and graduate student, was a great assistance in Cybex testing. Mark Haines, ATC, another athletic trainer and grad- uate student was very helpful in moving equipment and conducting vertical jump testing. David Fluker and John Slade, fellow athletic trainers, also provided great assistance in testing sessions. Spe- cial kudos go to Joann Janes, secretary in the exercise physiology research lab at Michigan State, for helping with endless details and for her incredible patience. Ellen Cassidy, athletic director at East Lansing High School, was of great help in securing administra- tive clearance to conduct the study. The varsity, junior varsity, and freshman basketball coaches at East Lansing High School were incredible cooperative and supportive; Gary Rider, varsity coach, Gary Greider, JV coach, and Diane Dockus and Mike Duffey, freshmen coaches. And the final vote of thanks must go to my parents, who were very supportive in a hectic time. TABLE OF CONTENTS Page LIST OF TABLES .............................................. vii CHAPTER I ................................................... 1 The Problem ............................................... 1 Purpose ................................................. 2 Research Hypotheses ..................................... 2 Research Plan ........................................... 2 Limitations of Research Plan ............................ 3 Significance ............................................ 3 CHAPTER II .................................................. 4 Review of Related Literature .............................. 4 Effects of Strength Training ............................. 4 Cellular Level ........................................ 4 Measurement of Strength and Power ....................... 7 Weight Training Programs ................................ 11 Isometric Training .................................... 11 Isotonic Training ..................................... 13 Isokinetic Training ................................... 14 In-season Weight Training ............................... 15 Strength Training in Adolescents ........................ 16 CHAPTER III ................................................. 18 Procedure ................................................. 18 Sampling ................................................ 18 Height-training Program ................................. 19 Testing ................................................. 19 Cybex Testing ......................................... 20 Vertical Jump Testing ................................. 20 CHAPTER IV .................................................. 22 Results and Discussion .................................... 22 Body Height ............................................. 22 Peak Torque ............................................. 22 Power ................................................... 33 Discussion of Results ..................................... 41 CHAPTER V ................................................... Summary, Conclusions, and Recommendations ................. APPENDIX - Raw Data Tables .................................. BIBLIOGRAPHY ................................................ vi 45 45 48 52 \DG’NO‘U‘I-DWN NHt—IO—DO—II—IO—OHHHh—l OOQNO‘U‘#WNHO LIST OF TABLES Control Group Body Height ...................... Experimental Group Body Height ................. Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Gain Score Score Score Score Score Score Score Score Score Score Score Score Score Score Score Score Score Score DI-DZ 01-02 01-02 01-02 02-03 D2-D3 D2-D3 02-03 02-03 02-03 02-03 02-03 01-03 01-03 01—03 01-03 01-03 Dl—D3 GOO/second Extension .......... 60°/second Flexion ............ 240°/second Extension ......... 240°/second Flexion ........... 60°/second Extension .......... 60°/second Flexion ............ 240°/second Extension ......... 240°/second Flexion ........... Total Power ................... Power/kg Body Height .......... Variance Testing .............. t-tests ....................... GOO/second Extension .......... 60°/second Flexion ............ 240°/second Extension ......... 240°/second Flexion ........... Total Power ................... Power/kg Body Height .......... vii 23 23 23 24 24 24 25 25 25 26 26 26 27 28 29 29 29 30 30 30 Iablg 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 Gain Score Dl-D3 Variance Testing .............. Gain Score Dl-D3 t-tests ....................... Gain Score Dl-DZ Total Power ................... Gain Score Dl-DZ Power/kg Body Height .......... Gain Score Dl-DZ Variance Analysis ............. Gain Score Dl-DZ t-tests ....................... Control Group GOO/second Flexion ............... Control Group 240°/second Extension ............ Control Group 240/second Flexion ............... Control Group Total Power ...................... Control Group Power/kg Body Height ............. Control Group GOO/second Extension ............. Experimental Experimental Experimental Experimental Experimental Experimental Group 60°/second Extension ........ Group 60°/second Flexion .......... Group 240°/second Extension ....... Group 240°/second Flexion ......... Group Total Power ................. Group Power/kg Body Height ........ viii 31 32 34 34 35 36 37 37 37 38 38 38 39 39 39 40 40 40 CHAPTER I THE PROBLEM Weight training is currently a well-known and widely accepted component of athletics and physical education. Many studies that have been conducted on weight training show that it can be a great aid in building and maintaining strength, power, endurance, and speed.5’7’8’9’1°’11’12’15’19’30’21’28’29’30’70’77 Weight training also can be a great aid in the prevention of athletic injury.14 With this in mind, it would seem logical to want to extend these benefits to high school sports, which involve a great propor- tion of this country’s active, competitive athletes. However, com- paratively few studies have been performed with high school athletes as opposed to other populations, e.g. college athletes. Pitman58 and Kusinitz and Keeney46 have found that weight training can improve strength and motor performance in adolescents. Fisher,32 however, found that no significant differences in strength or per- formance resulted from adolescents participating in a weight train- ing program. There also have been few studies done on how to maintain strength during a competitive sports season. Many coaches are hesi- tant to commit a great deal of time during a season for strength 37 training due to time and fatigue considerations. Guess and Colemanzz, however, have shown that strength training can be quite l beneficial in maintaining strength levels. Again, few if any stud- ies have been performed on high school subjects in this area. Purpose The purpose of this study was to provide information on the effects of in-season weight training on high school athletes. Eleven male high school athletes at East Lansing High School in East Lansing, Michigan, volunteered to serve as subjects. They were not involved in weight training programs prior to the season. Two com- parison groups, weight training and non-weight training, were formed. Leg peak torque and power were analyzed. Research Hypotheses The following hypotheses were tested during the course of this investigation: 1. A decline in peak torque and power will occur in the con- trol group as the season progresses. 2. The weight training group will maintain pre-season levels of peak torque and power, and may increase these levels somewhat as a result of weight training. Research Elan Two comparison groups were used in an ex post facto one-way design. The control group contained seven subjects and the experimental group four. Each subject underwent isokinetic testing of the knee joint of his dominant leg, at speeds of GOO/second and 240°/second. Each subject performed five repetitions at each speed. Peak torque values for leg extension and flexion were analyzed. Total leg power and power/kilogram of body weight were analyzed from a vertical jump test. Limitations of Research Elan The results of this study can be generalized only to the age range and sport involvement of the subjects. A given subject may not have been able to achieve 240°/second angular velocity quickly enough for accurate peak torque values to be recorded. Each subject was encouraged to put forth his best effort dur- ing both testing and weight training; however, there was no method available to ensure that they did so. The necessarily small sample size may have limited the results of the study. Signifisanse This study was designed to aid in the assessment of the value of weight training to high school age athletes, with an emphasis on the value of in-season weight training. The results of this study may help to determine training loads and methods of strength train- ing during the season. CHAPTER 11 REVIEW OF RELATED LITERATURE There are five areas of literature related to in-season strength training that shall be reviewed: 1) The effects of strength training, 2) methods of measuring and assessing strength and power, 3) previous studies in strength training during a compet- itive season, 4) methods of strength training, and 5) strength training in adolescents. ffe t 0 tr h r i l v 1 One well-known and commonly documented effect of strength training is an increase in muscle size and girth. Two mechanisms have been suggested for this phenomenon: hypertrophy (enlargement of the muscle fiber) and hyperplasia (increase in the number of mus- cle fibers). The hypertrophy theory currently is believed to be the most accurate.30 Hypertrophy was first explained by Morpugo in 1897. Morpugo found that there was no increase in the number of muscle fibers in dogs after two months of running exercise, although the muscle itself increased significantly in size.68 A possible mechanism of hypertrophy has been proposed by Goldsberg et al,34 with the increase being due to increased protein synthesis and increased amounts of noncontractile tissue (e.g., connective tissue) being formed. Goldsberg tends to rule out the endocrine system as being of great influence, and as another interesting finding states that the rate of protein synthesis does not appear to be increased. These conclusions were confirmed in part by Van Linge,74 who noted in studies an albino rats that in trained muscle the muscle weight doubled and was able to generate three times its normal force. Van Linge also noted increased protein synthesis and increased amounts of connective tissue between the muscle fibers. However, Van Linge went further in noting an increase in muscle fibers as well. Gonyea et al, 35 also reported an increase in muscle fibers in cats after heavy resistance training. deVries3o questions whether or not actual mitotic cell division has been found, so hyperplasia is still a controversial model for muscular size increase due to training. Another cellular change that results from strength training is a selective increase in the size of Type II (fast twitch) fibers. Thorstensson72 noted selective hypertrophy of Type II fibers, although he does not specify whether Type 11A or Type IIB fibers are selectively increased in size. Still another cellular change that occurs due to strength training is an increase in the levels of activity of certain enzymes. Costill et al.24 noted significant increases in gly- colytic, ATP-PC, and Krebs' Cycle enzyme activity with a training program of repeated 30-second bouts of maximal isokinetic exercise. In six-second bouts, however, increases were only noted in muscle phosphofructokinase. This led Costill to postulate that levels of activity probably are more related to duration of exercise than to intensity of exercise. In addition to having effects on the muscle fiber directly, strength training also appears to enhance neuromuscular control and electrical activity within the muscle. Moriteni and deVries53 found that after eight weeks of progressive resistance exercise, both neu- ral and hypertrophic factors combined to cause a strength increase. In this study, as the strength of the subjects increased, the slope coefficient of the electromyogram (EMG) was found to decrease, an indication of more efficient electrical activity. Cross-sectional area of the exercised muscle was found to increase. In addition, the contralateral limb also showed significant strength gain, although cross-sectional area and EMG slope coefficient did not change. It was concluded that the neural factors are most important in the early development of strength gain and that hypertrophic fac- tors gradually take over. This finding is confirmed by Hakkinen and Komi,38 who tested 14 male subjects during a 16-week weight training program and eight weeks of detraining afterwards. It was found that neural factors were affected first, then fiber diameter. The major- ity of the changes occurred in the first half of the training pro- gram. Detraining is found to reverse the effects of the training program, again affecting neural factors first then fiber diameter. The majority of the changes occurred in the first half of the detraining process. Other tissues are affected by strength training as well. Bones develop structural changes depending on where the bone is stressed most, with increased deposition of mineral and bone matrix in those areas. Ligaments and tendons develop more strength at their attachments. 0n the articular surface of-joints, cartilage tends to thicken in proportion to the increased load.12 The results of weight training in terms of performance, particularly regarding strength, are well documented. Significant gains in strength have been reported in isometric, isotonic and isokinetic programs.16’19’46’6’53’52’57’48’21’29’9’62’72’38’24’17 The applicability of these various programs to sports is still open to question. Isotonic and isokinetic programs seem to improve athletic power,19’26’47 whereas isometric training programs do not?”8 These power improvements seem to be specific to joint speeds at or below the speed of training.26’47 One of the traditional arguments against weight training is that it tends to make an athlete "muscle-bound," thus decreasing the athlete’s speed. This was disproved by Zorbas and Karpovich,46 who showed that a group of weight lifters could perform a speed task faster than a control group of non-lifters. Clarke and Henry20 also showed that speed is improved by strength training. Mea urement of tren th an ow Several operational definitions of strength have been offered for various sport activities. Choodinov18 defined absolute strength as maximum muscular strength without consideration of body weight. This definition could be used in relation to events such as the shot put or hammer throw. Relative strength is expressed as the ratio of maximum muscular strength to body weight. Events using relative strength are running and jumping. Berger12 expands these defini- tions. Absolute strength can be defined as strength in moving a heavy object other than body weight. It is measured by application of muscular force to an external object such as a strain gauge or dynamometer. Relative strength is strength used in moving body weight and can be measured by exercises such as chins and dips. Absolute power is the strength or force involved in moving an external object quickly. An example is the shot put. Relative power is strength used in moving body weight rapidly. It is perhaps the measurement of power most pertinent to sports situations. Rela- tive power is measured by such motor performance tests as the 50- yard dash and the vertical jump. Absolute strength can be measured isometrically, isotonically, or isokinetically. An isometric contraction of muscle occurs when force is exerted but muscle length does not change. Common methods of isometric measurement use cable tensiometers and strain gauges. Kennedy45 has found that the outputs of these devices correlate very well with each other and also with measures of maximum isotonic strength. He also found that the measurement results were dependent upon factors of subject selection and investigator experience. Bender and Kaplan5 evaluated the Multiple-Angle Testing Method for isometric strength testing. In this procedure, the subject exerts maximum voluntary isometric contractions at several points in the range of motion. Bender and Kaplan found this method to be reliable in most isometric testing. The disadvantage of the method is that it does not give a strength value for the whole range of motion, only at preselected points. Isotonic testing, which involves the application of muscular force against a constant resistance through a range of motion, is widely used in the coaching profession as a method of determining performance levels and improvements. For scientific purposes, how- ever, the method is not reliable because the testing involves guess- ing the subject’s repetition maximum (RM).3o Generally, an attempt is made to predict the subject’s l-RM load, and testing begins slightly below that weight so that the subject can work up to maxi- mum weight. This procedure can require a number of trials for the l-RM load to be established and subject fatigue can greatly influ- ence the final result. A further disadvantage to isotonic testing is that in most cases the test involves a sport-specific skill, e.g., the bench press. The subject’s previous experience in such skills also will influence the results of the testing, with a less experienced subject not being able to lift as much as he/she might after motor learning has taken place. The use of isokinetic exercise recently has become a very popular method of both testing and training. An isokinetic contrac- tion occurs when a muscle exerts force, either concentrically or eccentrically, at a constant velocity.30 The reliability of the isokinetic method has been established by Molnar.so Pilot tests of 46 children showed a very high test-retest reliability. In a later 10 study, Molnar et 31.51 found that different behavioral and technical aspects of testing caused no significant variations in testing results. Other investigators, however, have found that procedural and physical errors can greatly bias results if not corrected. For example, Winter at al.76 found that gravitational effects could pro- duce significant errors in peak torque measurement. This effect can be corrected mathematically by taking into account the weight of the limb and the effect of gravity on it.4°’52 Another error which can occur is more technical in nature. Sapega et al.62 found that during isokinetic testing an ”overshoot" phenomenon can occur at the end of the free acceleration period when the resistance mechanism engages. This effect was found to produce a spike on the recording graph immediately before formation of the torque curve. Investigators must be careful not to include the spike in their torque calculations, as the spike represents inertial forces and not muscular tension.62 ,Sinacore et al.,63 found that increasing the damp of the machine aids in reducing "overshoot" and in identifying peak torque. Increased damp also has the effect of shifting the torque curve to the right.62 This can result in decreased measurement of peak torque because the torque curve seems to appear later in the range of motion. Sinacore emphasized the importance of keeping the damp settings constant during testing, recording the damp settings for future reference and reproducibility of results, and being familiar with the damping effects of available equipment.63 11 Other factors, both physical and psychological, are involved in the expression of a subject’s strength, particularly in the case of adolescents. Tabin et al.71 and Maughan et al.48 both found that lean body mass correlates well with the maximum torque produced. These results appear to be confirmed by Watson and O’Donovan75 who found that all anthropometric measurements, except skinfolds, have positive correlations with strength. Skinfolds produced negative relationships. Ikai and Steinhaus44 found that psychological inhibition tends to be the limiting factor in the expression of strength. It was shown that stimuli which cause the inhibition to be inhibited, such as a close proximity gunshot or a hypnotic suggestion of strength, all caused temporary increases in strength. The opposite effect also takes place. When a stimulus that increases the normal inhibi- tion occurs, such as a hypnotic suggestion of weakness, then strength tends to decline. Weight Iraining Erograns Isnnatnic Training An isometric contraction is the exertion of force by a muscle without change in muscle length. In early research on muscle strength and strength training, isometric training was studied most. Hettinger and Muller were the pioneers in this early research. Hettinger41 found that one isometric contraction per day at 40-50% of maximal strength is sufficient to cause an increase in muscle strength. Earlier work by Hettinger and Muller indicated that one 12 contraction per day at two-thirds maximum strength for six seconds is best for promoting strength gains. It was found that greater force, number of repetitions, or duration of contraction do not seem to change the rate of strength gain.30 In later work, Muller55 found that the rate of gain with maximum exercise increases at 12% of maximum strength per week up to approximately 75% of maximum strength. Thereafter, the rate of strength gain declines exponeno tially as the level of strength approaches 100% maximum. Muller also reported that a maximal muscle contraction causes a prolonged stimulus for the development of contractile tissue that lasts approximately seven days.55 An additional finding was that detrain- ing causes a strength decrease of approximately 5% per day. Muller and Rohmert30 suggest that five to ten daily repeti- tions of a maximal contraction held for five seconds provides the most effective protocol for isometric strength development. Muller54 cited several advantages for isometric training. First, the method saves time and money by keeping equipment simple and by using only one contraction a day. Muller also stated that fatigue would not necessarily occur because only one contraction a day was needed to build strength and that the heart and circulatory systems were not stressed by isometric exercise. These latter suggestions, particularly those regarding the heart, have been disputed in recent literature.30 Without having comparisons to other types of training in their work, Hettinger and Muller have left themselves open to the criti- cism of other investigators. One of the major arguments is that 13 isometric training has poor applicability to sports and athletics. Berger8 and Ball et al.3 found that static training causes increases in strength but not in vertical jumping ability. A possible reason for this is the specificity of isometric training which promotes increases in strength at zero velocity and only at the specific joint angle to which resistance is applied.5’30 Wining An isotonic contraction involves a muscle producing force while its length changes. If the muscle shortens during the con- traction, a concentric contraction occurs; if the muscle length increases while force is produced, an eccentric contraction is tak- ing place. Isotonic methods of strength training probably are the most frequently used in sports and athletics. DeLorme,29 who was among the first to systematize isotonic strength training as a means of inducing muscular strength gain and hypertrophy, dubbed his program ”progressive resistance exercise.” Isotonic exercise has the advantage of being less specific to joint angles than is isometric exercise.28 That is, the contraction may take place throughout the entire range of motion. With this advan- tage, however, comes the problem of finding optimum exercise loads and regimens for maximum strength gains. DeLorme29 at first sug- gested 70-100 repetitions, but later reduced this number to 20-30.4 This is now the accepted number of repetitions used in most isotonic rehabilitation programs. In terms of sports, Berger10 found that a 14 smaller number of repetitions, between three and nine per set with an average of three sets, is better for building strength. In terms of exercise load, DeLorme4 found that one set of 10 repetitions at 1/2 10 RM followed by two sets of 10 repetitions at 3/4 10 RM and 10 RM produced significant gains and muscular hypertrOphy. Barney and Bangerter’s findings4 tend to support DeLorme. Berger11 finds that maximum or near maximum loads for exercise programs are more effective for producing strength. The DeLorme procedure seems most effective for producing muscular hypertrophy.4 The optimum frequency of workouts also is open to question, but appears to be between three and five times per week.33 Capen17 suggests that when using high loads with few repetitions one should work out only three times per week to ensure better recovery. Rasch and Morehouse59 and Darcus and Salter28 found that greater gains result from isotonic programs than from isometric programs. In contrast, Berger6 found that isometric training pro- duces more strength than does isotonic training. In later work, Rasch5°_concluded that strength may be gained by either isometric or isotonic exercise. Isntjnetic Training An isokinetic contraction occurs when a muscle shortens or lengthens at a constant angular velocity.43 If all factors causing variations of force are controlled, the muscle theoretically will contract at full capacity at all points in the range of motion. 15 One advantage of isokinetic training over isometric and iso- tonic training is its applicability to sports. Most sport movements take place at faster velocities than do weight training movements. It has been shown in studies utilizing isokinetic equipment that strength gains occur chiefly at velocities that are equal to or slower than the training velocity.26’57’47 This would tend to make isokinetic training superior to isometric and isotonic training. The research of Hutinger,42 Lesmes,47 and Pipes and Wilmore,57 tends to confirm this premise, although the latter study yielded contro~ versial results. The chief disadvantage of isokinetic training is the cost of the equipment which tends to be prohibitive on a large scale for most institutions. In-season Weight Training In contrast to the work done on weight training programs and the physiological effects of weight training, comparatively few studies have been done to determine the effectiveness of weight training during a competitive sports season. However, almost all the serious scientific work suggests that weight training should be an essential part of the in-season conditioning program. Campbell15 was among the first to study the effects of weight training during the season. Sixty-two college athletes were divided into two groups. At the beginning of their respective seasons one group began weight training in addition to their normal sports pro- gram. The second group participated only in regular practice and games. At mid—season the roles of the two groups were reversed, and 16 the nonlifting group began lifting. Campbell found that while the training procedures were more effective in the first half of the season, both groups had significantly higher performance on physical fitness tests while weight training. Guess37 studied the effects of in-season weight training on 60 college football players. It was found that those athletes who did not lift weights during the season sustained significant losses in strength compared to the lifting group. These findings were con- firmed by Coleman16 who studied 20 major league baseball players over the course of an 162—game season. At the end of the season, the training group was found to be significantly stronger and to have significant reductions in absolute body fat and relative body fat as well as increased lean body mass. A point of uncertainty exists in the optimum number of work- outs per week during the season. While most sourceszz’miz’39 advo- cate two sessions per week. Guess37 maintains that one per week is sufficient. Strength Training in Adglesgents Few studies have specifically been aimed at adolescent weight training. It has been speculated that adolescents cannot gain as much hypertrophy and muscular development as more mature subjects can.30 The primary reason for this is a lower level of testosterone secretion before puberty. Questions also have been raised about the safety of weight training for adolescents.13 17 The studies done in this area vary in results. Kusinitz46 demonstrated significant increases in scores of performance tests such as push-ups and pull-ups. Anthropometric gains, although small, were statistically significant. Pitman’s58 findings tend to confirm these results. Fisher,32 however, found that while gains in strength and anthropometric measurements were made, they were not significantly different from control subjects who participated in an exercise program that did not include weight training. Of these studies, only one injury was reported in almost 200 participating subjects. This suggests that weight training can be safe for ado- lescents if they are properly supervised. CHAPTER III PROCEDURE mm Twelve male high school athletes volunteered to participate in this study. All had been medically cleared to participate in high school athletics. All subjects were in ninth and tenth grade and were participants on the high school basketball team corresponding to their levels in school. Informed consent was obtained from the athletes and their parents prior to the beginning of the study. The subjects were divided into control and experimental groups with a stratified technique. The subjects were first classified by the position they played on the basketball team: guard or forward/center. The subjects then were divided further by their school grade so that there were four groups total: a) ninth-grade guards, b) ninth—grade forward/centers, c) tenth-grade guards, and d) tenth-grade forward/centers. The members of each group then were randomly assigned to the control and experimental groups. The phys- ical characteristics and abilities of the subjects were assumed to be normally distributed within their respective populations. No attempts were made to match subjects by body weight or basketball skill level. 18 19 flaight-training Prognan The control subjects participated only in regular team prac- tices and games. Those subjects assigned to the experimental group trained with weights twice a week in addition to the regular prac- tice routine. The weight workout was confined to the lower extrem- ities and consisted of leg press, quadricep extension, and hamstring curl exercises. The subjects performed three sets of eight repeti- tions at the 8-RM load which was established in a testing session prior to beginning the weight training program. Weight training sessions were held after practice twice a week. Subjects were dropped from the study if they missed more than four consecutive training sessions. One subject who did miss all sessions of the weight program had data that were acceptable for use in the control group, so he was reassigned there to replace one subject who was forced to leave due to injury. The remaining subjects were able to successfully complete the study. Progress was noted on individual charts. Data were collected on the control subjects only at regular testing sessions. Te n The leg strength and power of the athletes were tested by a standard protocol on the Cybex II dynamometer and by a vertical jump test. A total of three testing sessions were held, one at the beginning, middle, and end of the competitive season. Testing ses- sions were conducted by the same personnel who fulfilled the same duties each time. The two tests will be dealt with separately here. 20 Cybex Testing Testing was conducted within a week of the targeted date for each testing session. The equipment consisted of a Cybex II ' dynamometer with a Cybex data reduction computer. Before testing commenced, all equipment was calibrated to the manufacturer's stan- dards. The subjects were required to warm-up prior to testing by riding an exercise bicycle for five minutes and by performing exer- cises for approximately the same amount of time. Each subject then was seated on the testing apparatus and secured to it by means of restraining straps placed on the chest, abdomen, upper thigh, and ankle. The straps served the purpose of isolating the appropriate muscle groups. Damping and torque scale settings were kept constant for all subjects. All apparatus settings, such as torque arm length, were noted at the initial testing session for each subject and were reproduced for later testing. Backboards were placed beneath the subject’s lower back for additional comfort when neces- sary. Backboard conditions were reproduced at subsequent testing sessions as well. Each subject was required to perform five repeti— tions at 60°/second and five repetitions at 240°/second with their dominant leg. The peak torque was recorded for each speed. Gravi- tational effects were accounted for by weighing the limb prior to testing in accord with standard Cybex procedures. Vertical Jump Tasting Testing was conducted within a week of the targeted date. The testing apparatus is a unit constructed by Smoak66 which is designed 21 to measure the distance through which the subject accelerates prior to take-off in a vertical jump and thus to give a true indication of the leg power generated during the jump. Two measurements are recorded: one measures the crouch of the subject prior to jumping, the second measures the actual jump height. The point of measure- ment is on the subject’s back at the level of the center of gravity where two measuring tapes are attached. The subject is required to perform three jumps at each testing session with the best jump being used. CHAPTER IV RESULTS AND DISCUSSION Bod Wei ht Subject body weight did not change significantly in either group. In the control group, weight decreased between the second and third test sessions, but increased slightly betWeen the first and second, with a slight overall increase noted (see Table I). In the experimental group, body weight again showed a slight overall increase, with an insignificant decrease between the first and sec- ond test sessions, and a slight increase between the second and third (see Table 2). No attempts were made to control subject body weight through diet or exercise. Pea o e In leg extension and flexion at GOO/second, gain score calcu- lations and comparative t-tests revealed no significant gains or losses in peak torque when the groups were compared. No significant gains or losses were noted within either group. In the control group, an insignificant increase was noted in both extension and flexion between the first and second test sessions (see Tables 3-6), with insignificant gains being made between the second and third test sessions and over the length of the study (see Tables 7-22). In the experimental group, insignificant increases were noted in leg 22 23 Table 1. Control Group Body Weight Test Session i. sum x2 s2 s 1 137.29 1431.4 238.57 15.45 2 139.57 1505.68 250.95 15.48 3 138.86 1098.86 183.14 13.53 Table 2. Experimental Group Body Weight Test Session Ii sum x2 s2 s 1 153.5 629 209.67 14.48 2 152.5 561 187 13.67 3 154.5 702.81 234.27 15.31 Table 3. Gain Score 01-02 GOO/second Extension Test Session Y. sum x2 s2 s Experimental 3 582 194 13.93 Control -6.57 345.68 57.61 7.59 24 Table 4. Gain Score Dl-DZ 60°/second Flexion Test Session ii sum x2 s2 5 Experimental 3.75 504.74 168.25 12.97 Control -O.14 310.86 51.81 7.20 Table 5. Gain Score 01-02 240°/second Extension Test Session 7' sum x2 s2 5 Experimental -1 6 2 1.41 Control 0.14 130.86 21.81 4.67 Table 6. Gain Score Dl-DZ 240°/second Flexion Test Session I. sum x2 52 s Experimental -0.5 125 41.67 6.46 Control 2 142 23.67 4.87 25 Table 7. Gain Score 02-03 60°/second Extension Test Session i' sum x2\ 52 5 Control 9.42 410.74 58.48 8.27 Experimental -0.75 168.74 56.25 7.50 Table 8. Gain Score 02-03 60°/second Flexion Test Session RD sum x2 52 5 Control 3.71 359.40 59.9 7.24 Experimental .25 314.74 104.91 10.24 Table 9. Gain Score 02-03 240°/second Extension Test Session X. sum x2 52 5 Control 2.29 55.4 9.23 3.04 Experimental 5.25 46.74 15.58 3.95 26 Table 10. Gain Score 02-03 240°/second Flexion Test Session i' sum x2 s2 5 Control -4 292 48.67 6.98 Experimental .25 109 36.33 6.03 Table 11. Gain Score 02-03 Total Power Test Session 'Y sum x2 52 5 Control -40.71 45477537 757959.55 870.61 Experimental -20.67 1872010.4 936005.21 967.47 Table 12. Gain Score 02-03 Power/kg Body Weight Test Session I. sum x2 s2 5 Control -0.79 919.93 153.32 12.38 Experimental -3.5 226.02 113.01 10.63 27 mm» mm» mm» mm» mm» mm» mu:~_cm> pmacm o~._ m~.~ em.~ mo.o m~._ em.e u mm.o~ mm.mmm.~m~ mm.om m~.m m.mm m~.om Wm mm.- H~.moo.omm no.m¢ m~.mm _m.¢o_ m¢.mm Mm mx\cmzaa gmzoa pupae .xmpu xoe~ .axu xoeu .xmpm Rom .uxu Rom mcpammp mucapc~> mo-~o «scum cmmu .m~ mpnap 28 o: o: a: O: o: o: mucmgmkmwfi— a=a6_cpcmmm mm.o- o~.° - am.o He." ca.o- No.N- a mm.m- so.~o~- mN. - m~.m mN. ma. - am 2.? :8 - 5. mg :8 N; E a¥\gazoa aazoa .aaah .xa_a xoa~ .axu xoe~ .xaPI gem .qu no» manna-» mo-~o macaw ceaa .2 open... 29 Table 15. Gain Score 01-03 60°/second Extension Test Session X sum x2 52 5 Control 2.86 454.86 75.81 8.71 Experimental 2.5 419.27 139.75 20.48 Table 16. Gain Score 01-03 60°/second Flexion Test Session ‘I sum x2 52 s Control 3.57 793.68 132.28 11.50 Experimental 4 276 92 9.59 Table 17. Gain Score 01-03 240°/second Extension Test Session i. sum x2 52 5 Control 2.43 86.03 14.34 3.79 Experimental 4.25 21 7 2.65 30 Table 18. Gain Score 01-03 240°/second Flexion Test Session Y' sum x2 52 5 Control -1 778 129.67 11.39 Experimental -3 277 92.33 9.61 Table 19. Gain Score 01-03 Total Power Test Session 7' sum x2 52 5 Control 553.43 5597517.7 1099602.9 1048.62 Experimental 280.67 10488127 522406.33 724.16 Table 20. Gain Score 01-03 Power/kg Body Weight Test Session 2' sum x2 52 s Control 8.2 1430.16 238.36 15.44 Experimental 3.83 300.72 150.36 12.26 31 mm» mm» mm» mm» mm» mm» mucmwgm> peace mm.~ m~.e ow.“ vo.~ ev._ mm.m n om.om_ a.~oommo_ mm.~m 5 mm "m.m~ mm mm.mm~ mm.oo¢e-m so.a- om.¢~ m~.~m~ -.m~e Mm mx\cmzom cmzog page» .xmpu goow .uxm Roeu .xm—n goo .axu goo acaummp mucmwga> mc-_o msoom :wmo .- wpnah 32 a: o: o: o: o: o: 853:3 acauacpcupm ”5.8- a..c - Hm.o- m~.o- No.9 no.9 - a ma.” No.om~ m- m~.¢ a m.~ an ~.m m¢.mmm a- m..~ am.m mm.~m an mx\gazaa cazoa _aaop .xa_u xoa~ .uxu AOSN .xapa goo .axu goo mummy; 8-3 mgcum Emu .NN as: 33 flexion during all phases of the study (see Tables 4, 7, and 16). In leg extension, insignificant increases were noted overall and between the first and second test sessions (see Table 3), with an insignificant decrease evident between the second and third test sessions (see Table 7). In leg extension and flexion at 240°/second gain scores and comparative t-tests showed no significant increases or decreases when the two groups were compared. The experimental group showed a net decrease in peak torque at 240°/second of leg flexion (see Tables 6, 10, and 18), both between testing sessions and for the study as a whole. In leg extension at 240°/second, the experimental group showed an initial decrease in peak torque between the first and second test sessions, but showed gains between the second and third test sessions and for the duration of the study (see Tables 5, 9, and 17). The control group showed insignificant gains in peak torque at 240°/second of leg extension, while insignificant decreases were noted for 240°/second leg flexion over- all and between the second and third test sessions, with an insignificant increase between the first two sessions. Variance analysis and t-tests for gain scores 01-02 are found in Tables 25 and 26. Means, variances, and standard deviations are found in Tables 27-38. Ennan Both groups showed insignificant increases in both total leg power and leg power/kg of body weight. The control group showed the greater increase, although the difference was found to be nonsignif- icant (see Tables 37, 38, 23, 24, 11, 12, 19, and 20). 34 Table 23. Gain Score 01-02 Total Power Test Session i' sum x2 s2 5 Experimental 567.5 1329945 443315 665.82 Control 462 1179088 196514.67 443.30 Table 24. Gain Score 01-02 Power/kg Body Weight Test Session Y' sum x2 52 s Experimental 8.15 308.8 102.93 10.15 Control 9 385.68 64.28 8.02 35 mm» mm» mm» o: mm» mm» mampmacm oa.~ a~.~ ea._ ~m.o~ 5N.m am.m a ¢~.¢o no.e_mam_ No.m~ N _m._m ~G.Nm Wm mm.~o~ mammea No.15 _m._~ m~.wo~ ea“ Mm a¥\cazoa _cazaa .aaop .xa_u eoe~ .axw xoew .xa_a gem .axu goo m.m»p~=< mucmmga> Na-~a macaw =.aa .mN m—nmp 36 .ammunu XOUumcagsuou a m-. commcwuxm ROQN ma “mm“-..— 9:...” o: o: o: o: o: o: mucwcmeemo Samoacmcmwm 2.? N2 :5- $5- $8 :3 3 m; :8 m8- 7 m; M No. a S. N :5 :5- $8- 6 9:85. 5.5.. 38 as: as: tea as: as: .8... .3 .3... 3mm»-..— ~o-3 28m 58 .3 m3: 37 Table 27. Control Group 60°/second Flexion Test Session 7' sum x2 s2 s 1 75 2180 363.33 19.06 2 74.86 1250.86 208.48 14.44 3 78.57 1483.68 247.28 15.72 Table 28. Control Group 240°/second Extension Test Session '7 sum x2 52 s 1 78 584 97.33 9.87 2 78.14 484.86 80.81 8.99 3 80.43 427.68 71.28 8.44 Table 29. Control Group 240°/second Flexion Test Session 7. sum x2 52 s 1 47.43 1255.68 209.28 14.47 2 49.43 697.68 116.28 10.78 3 46.43 337.68 56.28 7.50 38 Table 30. Control Group Total Power Test Session '7 sum x2 52 s 1 3502.29 4191257.4 698542.9 8.82 2 4111.71 4614255.4 769042.56 876.95 3 4055.71 4008560.9 668093.44 817.37 Table 31. Control Group Power/kg Body Weight Test Session '7 sum x2 52 s 1 55.44 466.92 77.82 8.82 2 64.44 592.1 98.68 9.93 3 63.66 1588.81 264.80 16.27 Table 32. Control Group 60°/second Extension Test Session ‘7 sum x2 52 s 1 118.56 1506.86 251.14 15.8 2 116.57 947.68 157.95 12.57 3 126.00 830.00 138.33 11.76 39 Table 33. Experimental Group 60°/second Extension Test Session 7' sum x2 52 s 1 152 576 192 13.86 2 155 1190 396.67 19.92 3 154.25 1598.74 532.91 23.08 Table 34. Experimental Group 60°/second Flexion Test Session .7 sum x2 s2 s 1 86.5 153 51 7.14 2 90.25 882.74 294.25 17.15 3 90.5 261.00 87 9.33 Table 35. Experimental Group 240°/second Extension Test Session '7 sum x2 52 s 1 96 138 46 6.78 2 95 104 34.67 5.89 3 100.25 218.74 72.91 8.54 40 Table 36. Experimental Group 240°/second Flexion Test Session 7' sum x2 s2 s 1 ~ 57.5 41 13.67 3.70 2 57 90 30 5.48 3 54.5 141 47 6.86 Table 37. Experimental Group Total Power Test Session .7 sum x2 s2 s 1 4940.75 480498.74 160166.25 400.21 2 5508.25 2048814.7 682938.25 826.40 3 5393.67 1052788.7 526394.34 725.53 Table 38. Experimental Group Power/kg Body Weight Test Session '7 sum x2 52 s 1 71.63 355.00 118.33 10.88 2 79.78 444.40 148.13 12.77 3 80.23 78.81 39.41 6.28 41 DISCUSSION OF RESULTS The finding of no significant gains in peak torque for the experimental group makes it doubtful that two weight training ses- sions per week with three sets of eight repetitions at the 8-RM load are sufficient to build strength. This finding would tend to agree with those of others in the area. Berger9 noted that while strength gains could be made in two weeks, training twice weekly with a load of 2/3 I-RM, at least one maximal effort had to be made at a third weekly training session for the effect to occur. Berger added that the increase in strength with this particular training program was due largely to that maximal effort. Berger’s statement tends to support the earlier conclusion of Steinhaus66 that no matter how much a muscle is worked, it must be overloaded in order for strength gains to occur. In some later work, Berger and Hardage11 concluded that maximum or near maximum loads are necessary for optimal strength increases. This observation also was supported by Barney and Bangarter4 who showed that with heavier loads, greater gains in strength and hypertrophy could be made. While a strength loss in the control group was expected, that loss did not occur. Fisher32 obtained similar results in that a weight training group of junior high school athletes had scores on a standardized physical education test that were not significantly different from those of a control group performing the same test. This is in contrast to the findings of Pitman56 and Kusinitz and Keeney45 who found significant improvements in both physical fitness tests and anthropometric measurements. However, it is questionable 42 whether losses of strength reported in subjects who were not partic- ipating in weight training could be due to the attrition of the com- petitive season. The subjects in this study were not involved in a weight training program prior to the start of their season. Cole- man22 reported significant strength losses in major league baseball players who did not train as the season went on. These players did lift weights in their preseason training. This also was true in a study by Guess,37 who reported significant strength loss in college football players who did not train with weights during the season. In this study, the players had again lifted during preseason prac- tice, but stopped once the season began. The lack of strength loss in the control subjects of the present study tends to argue that the strength loss reported by Guess and Coleman probably is more from a detraining effect than the attrition of athletic competition. It should be remembered, however, particularly in the case of Coleman’s study, that the competitive season of those athletes is longer, and competition tends to be more intense than in high school sports. The weight training program in this study was designed to be a maintenance program. In view of this, nonsignificant or nonexistent losses of strength in the experimental group are not surprising. However, it should be noted that the control subjects did not suffer significant strength losses either. This tends to preclude the con- clusion that the weight program maintained the strength level of the experimental group. Both groups failed to increase peak torque at the 240°/second speed. This finding tends to confirm the theory of specificity of 43 training speed reported in previous work. Coyle et al.26 found that college men who trained isokinetically at fast speeds improved power at their training velocity and at all slower velocities, but those who trained at slow speeds only improved power at their training velocity. Lesmes et al.47 also found that training velocity is an important factor in power improvement. The lack of improvement in power by the experimental group was unusual in view of previous findings which showed weight training does improve power.15’19’8 Again, however, since the weight program was designed to be a maintenance program and did not produce signif- icant gains in peak torque for the experimental group, it is possi- ble that the program was not intense enough to produce gains in power either. An interesting observation is that the control group improved in leg power slightly (but nonsignificantly) more than did the experimental group. A possible explanation for this difference is to be found in the fact that the experimental subjects tended on the average to be physically more mature than the control subjects. The mean body weight of the control group was approximately 15 pounds less than that of the experimental group throughout the study. It is conceivable that during the season the smaller and less mature athletes gained power by a motor learning mechanism. This idea has support in the work of Moriteni and deVries53 and Hakkinen and Komi38 who showed that neural control tends to be one of the most important factors in early strength development due to training. Moriteni and deVries found that as strength increases the slope 44 coefficient of the electromyogram decreases, indicating greater efficiency of electrical activity. This could be the result of a more efficient pattern of motor unit recruitment in the involved muscles. In a sport where jumping predominates, such as basketball, the athletes receive continual practice at the skill during the sea- son and conceivably will improve as the neural recruitment pattern improves. Another factor that could have influenced final results was the motivation of the subjects. During the latter half of the sea- son, several subjects were heard to say that they were not as inter- ested in basketball as they had once been. Ikai and Steinhaus44 found that a key to the expression of human strength is the removal of inhibitions that prohibit this expression. Conversely, rein- forcement of this inhibition would tend to further mask strength expression. It is possible that an unmotivated subject will be more inhibited than a motivated subject. CHAPTER V SUMMARY, CONCLUSIONS, AND RECOMMENDATIONS Eleven high school basketball players were tested for leg extension/flexion peak torque and leg power at the beginning, mid- dle, and end of their competitive season. During the season, four of the athletes participated in a weight training program that con- sisted of two training sessions per week in addition to practice and games. The training load used was 8-RM for each subject, with an exercise regimen of three sets of eight repetitions. The other sub- jects participated only in regular practice and game activities. Peak torque and leg power were analyzed after all data were col- lected. Statistical analyses revealed no significant differences between groups in either peak torque or power. In addition, no sig- nificant changes were noted in peak torque or power within the com- parison groups during the study. The athletes were not involved in weight training programs prior to the season. In an unusual find- ing, the control group experienced a nonsignificant gain in leg power during the season. From these results the following conclusions were drawn: 1) Two weight training sessions per week with a regimen of three sets of eight repetitions with an 8-RM load is not sufficient to build significant amounts of strength. 45 46 2) A conclusion that the weight training program maintained prior strength levels is unjustified in this study because the con- trol group maintained strength and power levels successfully without a weight training program. 3) Losses of strength noted in previous in-season weight training studies probably are due to a detraining effect rather than to the attrition of sports participation. 4) An insignificant increase in control group leg power was possibly due to a motor learning effect from repeated jumping prac- tice as the season progressed. For future research, the following recommendations are made: 1) The study should be repeated with a larger sample size and with two full, comparable teams being used as subjects. In this way, team unity can be preserved and better comparisons made. 2) A study comparing a group that had lifted weights prior to the season with a group that had not would be a revealing test of the detraining vs. attrition theory. 3) Studies with a variety of age groups and weight training programs are needed to determine the efficacy of exercise regimens for in-season weight training. 4) Testing should be conducted at medium speed Cybex set- ting, e.g. 180°/second, rather than 240°/second to avoid potentially misleading torque readouts due to the torque overshoot phenomena. 47 APPENDIX Raw Data Tables 448 RAW DATA TABLES Peak Torque is in ft./1bs. Power is watts. Power/kg. is in watts/kg. body weight CONTROL SUBJECT a; 60% ext./6o% flexion/240% ext./24ot flexion/Total Power/Power/kg. 1) 136 83 81 52 3687 54.9 2) 124 86 80 53 4623 68.3 3) 141 91 85 53 4642 69.1 oa-o1) 5 a 4 1 955 14.2 D2-D1) -12 3 -1 1 936 13.4 D3-DZ) 17 5 5 0 19 0.8 CONTROL SUBJECT a; 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 117 87 83 61 3980 62.6 2) 104 74 77 58 4985 78.4 3) 113 76 83 46 3897 63.6 D3-Dl) -4 -11 0 -15 -83 1.0 D2-Dl) -13 -13 -6 -3 1005 15.8 03-02) 9 2 6 -12 -1088 -14.8 CONTROL SUBJECT a; 60% ext. 604 flexion 240% ext. 240% flexion Total Power Power/kg. 1) 147 92 84 62 3905 61.4 2) 138 91 85 57 4128 62.7 3) 138 96 88 56 4103 62.3 D3-D1) -9 4 4 -6 198 0.9 DZ-Dl) -9 -1 1 -5 223 1.3 03-02) 0 -5 3 -1 -25 -0.4 CONTROL SUBJECT A; 449 60% ext. 60% flexion 240% ext. 240% f1exion Total Power Power/kg. 1) 100 36 56 19 1819 38.1 2) 104 47 61 26 2490 50.8 3) 110 55 64 38 2000 39.3 03-01) 10 19 8 19 181 1.2 D2-Dl) 4 11 5 7 671 12.7 03-02) 6 8 3 12 -490 -11.5 some was: 2:. 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 111 70 79 50 3167 51.7 2) 108 71 73 51 3413 55.3 3) 128 84 75 43 4195 68.4 03-01) 17 14 -4 -7 1028 16.7 DZ-Dl) -3 1 -6 1 246 3.6 03-02) 20 13 2 -a 782 13.1 c_o__mOL swag §_: 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 121 71 80 44 3551 55.9 2) 123 72 84 50 4728 74.4 3) 122 60 81 37 5995 91.7 D3-D1) 1 -11 1 -7 2444 35.8 DZ-Dl) 2 1 4 6 1177 18.5 D3-DZ) -1 -12 -3 -13 1267 17.3 CONTROL SUBJECT ll 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 130 86 83 44 4407 63.5 2) 115 83 87 51 4415 61.2 3) 130 88 87 52 3558 51.2 03-01) 0 2 4 8 -849 -12.3 D2-Dl) -15 -3 4 7 8 -2.3 03-02) 15 5 O 1 -857 -10.0 5C) EXPERIMENTAL SUBJECT 1; 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 156 94 99 62 4424 57.3 2) 177 114 99 60 5235 67.8 3) 185 103 101 ' 49 t . 03-01) 29 9 2 -13 . . 02-01) 21 20 o -2 811 10.5 03-02) 8 -11 2 -11 . . 8 Areas marked with asterisk were not recorded or computed due to ankle injury subject suffered the day before the last testing session. This data was not included in final calculations. EXPERIMENTAL SUBJECT 2; 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 156 82 92 59 4925 79.2 2) 143 73 91 54 4503 72.4 3) 136 85 95 55 4672 74.5 03-01) '20 3 3 -4 -253 -4.6 DZ-Dl) -7 '9 '1 '5 -422 -6.8 03-02) '7 12 4 '4 169 2.2 EXPERIMENTAL SUBJECT 2; 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 164 79 104 54 5018 69.1 2) 166 87 101 63 5877 84.0 3) 159 92 112 64 6123 87.0 03-01) '5 13 8 10 1105 17.9 DZ-Dl) 2 8 -3 9 859 14.9 03-02) -7 5 11 1 246 3.0 EXPERIMENTAL SUBJECT 4; 60% ext. 60% flexion 240% ext. 240% flexion Total Power Power/kg. 1) 132 91 89 55 5396 80.9 2) 134 87 89 51 6418 94.9 3) 137 82 93 50 5386 79.1 D3-Dl) 5 -9 4 '5 -10 '1.8 DZ-Dl) 2 -4 0 -4 1022 14.0 D3-DZ) 3 '5 4 -1 '1032 -15.8 51 BIBLIOGRAPHY 10. 11. BIBLIOGRAPHY Altug, 2., T. Altug, A. Altug. A Test Selection Guide for Assessing and Evaluating Athletes. National Strength and Con- ditioninq Assoc 9(3):62-66. Ash, David N. Asst. Strength and Conditioning Coach, Univer- sity of Iowa. Personal communication, September, 1987. Ball, Jerry R., George Q. Rich, Earl L. Wallis. Effects of Isometric Training on Vertical Jumping. Research Quarterly 35:231-235, 1964. Barney, V. S. and B. L. Bangerter. Comparison of Three Pro- grams of Progressive Resistance Exercise. Researgh Quartarly 32:138-146, 1961. Bender, J. A. and H. M. Kaplan. The Multiple Angle Testing Method for the Evaluation of Muscle Strength. Journal 9f Bone and Joint Surgery 45(1):]35-140, 1963. Berger, Richard A. Comparison of Static and Dynamic Strength Increases. Research Quarterly 33:329-332, 1962. Berger, Richard A. Comparative Effects of Three Weight Train- ing Programs. Research Quarterly 34:396-398, 1963. Berger, Richard A. Effects of Dynamic and Static Training on Vertical Jumping Ability. Research Quarterly 34:419-424, 1963. Berger, Richard A. Comparison of the Effect of Various Weight Training Loads 0n Strength. Research Quarterly 36:141-146, 1965. Berger, Richard A. Application of Research Findings in Pro- gressive Resistance Exercise to Physical Therapy. Journal of the Association for Physicalaand Mental Rehabilitation 19:200- 203, 1965. Berger, Richard A. and B. Hardage. Effect of Maximum Loads for each of Ten Repetitions on Strength Improvement. Research Quarterly 38:715-718, 1967. 52 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 53 Berger, Richard A. Applied Exercise Physiology, Lea and Febiger, Philadelphia, 1982. Brady, T. A., B. R. Cahill, L. M. Bodnar. Weight Training- Related Injuries in the High School Athlete. American Journal of Sports Medicine 10(1):1—5. Cahill, Bernard R. and Edward H. Griffith. Effect of Pre-Sea- son Conditioning on the Incidence and Severity of High School Football Knee Injuries. American Journal of Sports Medicine 6:180-183, 1978. Campbell, Robert L. Effects of Supplemental Weight Training on the Physical Fitness of Athletic Squads. Research Quar- terly 33:343-348, 1962. Capen, Edward K. The Effect of Systematic Weight Training on Power, Strength, and Endurance. Research Quarterly 21:83-93, 1950. Capen, Edward K. Study of Four Programs of Heavy Resistance Exercises for Development of Muscular Strength. Rasearch Quartarly 17:132-142, 1956. Choodinov, V. 1. Absolute and Relative Strength of Sportsmen. Theory and Practice of Physical Culture 3:26-29, 1962 [Russian]. Reviewed by Michael Yessis, Raaaargh Quarterly 35:332-333, 1964. Chui, Edward. The Effect of Systematic Weight Training on Athletic Power. Research Quarterly 21:188-194, 1950. Clarke, D. H. and F. M. Henry. Neuromotor Specificity and Increased Speed from Strength Development. Research Quarterly 32:315-325, 1961. Clarke, David H. and Alan G. Stull. Endurance Training as a Determinant of Strength and Fatigability. Resear h r r 41:19-26, 1970. Coleman, A. E. In-Season Strength Training in Major League Baseball Players. The Physician and Sportsmedigina 10(10):125-132. Considine, w. J. and w. J. Sullivan. Relationship of Selected Tests of Leg Strength and Leg Power on College Men. Research Quarterly 44:404-416, 1973. Costill, D. L., E. F. Coyle, w. F. Fink, G. R. Lesmes, and F. A. Witzman. Adaptations in Skeletal Muscle following Strength Training. Journal of Applied Physiology 46:96-99, 1979. 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 54 Counsilman, James E. Does Weight Training Belong in the Pro- gram? Journal of Health. Physical Education.,and Recreation 26:17-18, Jan. 1958. Coyle, E. F., D. C. Feinig, T. C. Rotkis, H. Cole, F. B. Roby, v. Lee, and J. H. Wilmore. Specificity of Power Improvements through Slow and Fast Isokinetic Training. Journal of Applied Physiology 51:1437-1442, 1981. Cratty, Bryant J. Transfer of Small-Pattern Practice to Large Pattern Learning. Research Quarterly 33:523-535, 1962. Darcus, H. D. and N. Salter. The Effect of Repeated Muscular Exertion on Muscle Strength. Journal of Physiology 129:325- 336, 1955. DeLorme, Thomas L. Restoration of Muscle Power by Heavy Resistance Exercises. Journal of Bone and Joint Surgery 27:645—667, 1945. deVries, Herbert A. Physiology of Exercise for Physical Edu- cation and Athletics, 4th ed. Wm. C. Brown Publishers, Dubuque, Iowa, 1986. Duchateau, J. and K. Hainaut. Isometric or Dynamic Training: Differential Effects on Mechanical Properties of a Human Mus— cle. Journal of Applied Physiology 56:296-301, 1984. Fisher, Arnold G. An Experimental Investigation of the Effects of a Weight Training Program on Underdeveloped Junior High School Boys. Unpublished Master’s Thesis, Sacramento State College, 1966. Gillam, G. M. Effects of Frequency of Weight Training on Mus- cle Strength Enhancement and Physical Fitness. Journal of Sports Medicine 21:432-436, 1981. Goldsberg, A. L., J. D. Etlinger, D. F. Goldspink, and C. Jablecki. Mechanism of Work Induced Hypertrophy of Skeletal Muscle. Medicine and Science in Sports 7:248-261, 1975. Gonyea, w., G. C. Ericson, and F. Bonde-Peterson. Skeletal Muscle Fiber Splitting Induced by Weight Lifting Exercise in Cats. Acta Physiologica Scandinavica 99:105-109, 1977. Grace, Thomas G., et al. Isokinetic Muscle Imbalance and Knee Joint Injuries. Journal of Bone and Joint Surgery 66Az734- 740, 1984. Guess, Liles C. A Comparison of Two Training Programs for Maintaining Increased Muscular Strength Developed during an 38. 39. 40. 41. 42. 43. 44. 45. 46. 47. 48. 49. 55 Off-Season Conditioning Program. Unpublished Master’s Thesis, University of Texas at Austin, 1967. Hakkinen, K. and P. V. Komi. Electromyographic Changes during Strength Training and Detraining. Medicine and Science in Sports and Exercise 15:455-460, 1983. Henry, David. Strength and Conditioning Coach, Michigan State University. Personal communication, Sept. 1987. Heusner, William W., Michigan State University. Personal com- munication, Sept. 1987. Hettinger, Theodor. Physiology of Strength. Charles C. Thomas, Springfield, Illinois, 1961. Hutinger, Paul W. Comparison of Isokinetic, Isotonic, and Isometric Developed Strength to Speed in Swimming the Crawl Stroke. Doctoral Thesis, Indiana University, Aug. 1970. Hislop, H. J. and J. J. Perrine. The Isokinetic Concept of Exercise. Physical Therapy 47:114-117. Ikai, M. and A. H. Steinhaus. Some Factors Modifying the Expression of Human Strength. Journal of Applienghysiolggy 16:157-163, 1961. Kennedy, W. R. The Development and Comparison of an Electri- cal Strain-Gauge Dynamometer and a Cable Tensiometer for Objective Muscle Testing. Archives of Physical Medicine and Rahabilitation, 46:793-803, Dec. 1965. Kusinitz, Ivan and Clifford E. Keeney. Effects of Progressive Weight Training on Health and Physical Fitness of Adolescent Boys. Research Quarterly 29:294-301, 1958. Lesmes, G. R., D. L. Costill, E. F. Coyle, and W. J. Fink. Muscle Strength and Power Changes during Maximal Isokinetic Training. Medigjne and Scienga in Sports 10:266-269. 1978. Maughan, R. J., Jennifer S. Watson, and J. Weir. Strength and Cross-Sectional Area of Human Skeletal Muscle. Journal of Physiology 338:37-49, 1983. McGovern, Richard E. and Harold B. Lusicombe. Useful Modifi- cations of Progressive Resistance Exercise Techniques. Archives of Physical Medicine and Rehabilitation 34:475-477, 1953. 50. 51. 52. 53. 54. 55. 56. 57. 58. 59. 60. 61. 62. 56 Molnar, Gabriella E. and Justin Alexander. Objective, Quanti- tative Muscle Testing in Children: A Pilot Study. Archivas of Physiaal Medicine and Rehabilitation 54:224-228, 1973. Molnar, Gabriella E., Justin Alexander, and Nicholas Gutfeld. Reliability of Quantitative Strength and Measurements in Chil- dren. Archives of Physical Medicine and Rehabilitatign 60:218-221, 1979. Monroe, Jeffrey S. Head Athletic Trainer, Michigan State Uni- versity. Personal communication, Sept. 1987. Moriteni, T. and H. A. deVries. Neural Factors versus Hyper- trophy in the Time Course of Muscle Strength Gain. Amarigan Journal of Physical Medicine 58:115-130. 1979. Muller, Erich A. The Regulation of Muscular Strength. Qogr- nal of the Association for Physical and Mental Rehabilitatigg 11:41-47, Mar.-Apr., 1957. Muller, Erich A. Influence of Training and of Inactivity on Muscle Strength. Archives of Physical Medicine and Rehabili- tation 51:449-462, 1970. Perrine, J. J. and V. R. Edgerton. Muscle Force-Velocity and Power-Velocity Relationships under Isokinetic Loading. Medicina and Science in Sports 10:159-166, 1978. Pipes, T. V. and J. H. Wilmore. Isokinetic Strength Training in Adult Men. Medicine and Science in Sports 7:262-274, 1975. Pitman, Joe. A Comparative Study of the Effects of a Weight Training Program on Junior High School Boys. Master’s Thesis, Stetson University, DeLand, Florida, 1959. Reviewed by P. J. Rasch in Research Quarterly 31:542, 1960. Rasch, P. J. and L. E. Morehouse. Effect of Static and Dynamic Exercises on Muscular Strength and Hypertrophy. J urn f Applied Physiology 11:29-34, 1957. Rasch, Philip J. Progressive Resistance Exercise: Isotonic and Isometric, a Review. Journalyof the Association for Phys- igal and Mental Rehabilitation 15:46-50, 56, 1961. Royce, Joseph. Reevaluation of Isometric Training Methods and Results: A Must. Research Quarterly 35:215-216, 1964. Sapega, Alexander A., James A. Nicholas, David Sokolow, and Anthony Saranniti. The Nature of Torque "Overshoot" in Cybex Isokinetic Dynamometers. Medicine and Science in Sports and Exercise 14:368-375, 1982. 63. 64. 65. 66. 67. 68. 69. 70. 71. 72. 73. 74. 75. 57 Sinacore, David R., Jules M. Rothstein, Anthony DeLitto, and Steven J. Rose. Effect of Damp on Isokinetic Measurements. Physical Therapy 63:1248-1250, 1983. Slater-Hammel, Arthur T. Bilateral Effects of Muscle Activ- ity. Research Quarterly 21:203-209, 1950. Smith, Michael J. and Paul Melton. Isokinetic versus Isotonic Variable-Resistance Training. American Journal of Sports Medicine 9:275-279, 1981. Smoak, Bonnie Lee. Strength and Power in Elite Swimmers. Doctoral Dissertation, Michigan State University, 1985. Starr, Isaac. Units for the Expression of both Static and Dynamic Work in Similar Terms and their Application to Weight Lifting Experiments. Journal of Applied Physiology 4:21-29, 1951. Steinhaus, Arthur H. Strength from Morpugo to Muller-A Half Century of Research. Journal of the Association for Physical and Mental Rehabilitation 9:147-151, 1955. Steinhaus, Arthur H. Toward an Understanding of Haalth app Ehygital Education, William C. Brown Co., Dubuque, Iowa, 1963. Stull, G. Alan and David H. Clarke. High-Resistance, Low-Rep- etition Training as a Determiner of Strength and Fatigability. Researth Quarterly 41:189-193, 1970. Tabin, G. C., John R. Gregg, and T. Bonci. Predictive Leg Strength Values in Immediately Prepubescent and Postpubescent Athletes. American Journal of Sports Medicine 13:387-389, 1985. Thorstensson, Alf. Observations on Strength Training and Detraining. Acta Physiologica Scandinavica 100:491-493, 1978. Thorstensson, Alf, Lars Larsson, Per Tesch, and Jan Karlsson. Muscle Strength and Fiber Composition in Athletes and Seden- tary Men. Medicineaand Science in Sports 9:26-30, 1977. Van Linge, B. The Response of Muscle t0 Strenuous Exercise. Journal of Bone and Joint Surgery 448:711-721, 1962. Watson, W. S. and D. J. O’Donovan. Factors Relating to the Strength of Male Adolescents. Journal of Applied Physiology 43:834-838, 1977. 76. 77. 58 Winter, D. A., R. P. Wells, and G. W. Orr. Errors in the Use of Isokinetic Dynamometers. European Journal of Applied Phys- iology 46:397-408, 1981. Zorbas, W. S. and P. V. Karpovich. The Effect of Weight Lift- ing upon the Speed of Muscular Contractions. Research Quar- terly 22:145-148, 1951.